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71.
Two cosolvent systems are studied by light scattering and viscosity measurements. The cosolvency mechanism is discussed in relation to the preferential adsorption, solubility parameter, and excess free energy of mixing of the two liquid components. The cosolvency effects are attributed to a “true” and an “apparent” cosolvency. 相似文献
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Kyriakos Keremedis 《Archive for Mathematical Logic》2001,40(8):569-580
We show that some well known theorems in topology may not be true without the axiom of choice.
Received: 29 August 1995 / Revised version: 23 June 2000 / Published online: 3 October 2001 相似文献
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Andrzej Gładysiak Dr. Tu N. Nguyen Dr. Mariana Spodaryk Dr. Jung-Hoon Lee Prof. Dr. Jeffrey B. Neaton Prof. Dr. Andreas Züttel Dr. Kyriakos C. Stylianou 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(2):501-506
A pyrene-based metal-organic framework (MOF) SION-8 captured iodine (I2) vapor with a capacity of 460 and 250 mg g−1MOF at room temperature and 75 °C, respectively. Single-crystal X-ray diffraction analysis and van-der-Waals-corrected density functional theory calculations confirmed the presence of I2 molecules within the pores of SION-8 and their interaction with the pyrene-based ligands. The I2–pyrene interactions in the I2-loaded SION-8 led to a 104-fold increase of its electrical conductivity compared to the bare SION-8 . Upon adsorption, ≥95 % of I2 molecules were incarcerated and could not be washed out, signifying the potential of SION-8 towards the permanent capture of radioactive I2 at room temperature. 相似文献
77.
Liu G Khlobystov AN Briggs GA Porfyrakis K 《Chemical communications (Cambridge, England)》2012,48(42):5148-5150
The decomposition mechanism of N@C(60) derivatives has been elucidated by DFT calculations, revealing different roles of the pendant groups in the escape course of the incarcerated nitrogen. Whereas the pyrrolidine group facilitates the inversion of the incarcerated nitrogen, the cyclopropane group prohibits this process. 相似文献
78.
George E. Magoulas Pantelis Afroudakis Kalliopi Georgikopoulou Marina Roussaki Chiara Borsari Theano Fotopoulou Nuno Santarem Emile Barrias Paloma Tejera Nevado Julia Hachenberg Eugenia Bifeld Bernhard Ellinger Maria Kuzikov Irini Fragiadaki Effie Scoulica Joachim Clos Sheraz Gul Maria Paola Costi Wanderley de Souza Kyriakos C. Prousis Anabela Cordeiro da Silva Theodora Calogeropoulou 《Molecules (Basel, Switzerland)》2021,26(14)
A library of seventeen novel ether phospholipid analogues, containing 5-membered heterocyclic rings (1,2,3-triazolyl, isoxazolyl, 1,3,4-oxadiazolyl and 1,2,4-oxadiazolyl) in the lipid portion were designed and synthesized aiming to identify optimised miltefosine analogues. The compounds were evaluated for their in vitro antiparasitic activity against Leishmania infantum and Leishmania donovani intracellular amastigotes, against Trypanosoma brucei brucei and against different developmental stages of Trypanosoma cruzi. The nature of the substituents of the heterocyclic ring (tail) and the oligomethylene spacer between the head group and the heterocyclic ring was found to affect the activity and toxicity of these compounds leading to a significantly improved understanding of their structure–activity relationships. The early ADMET profile of the new derivatives did not reveal major liabilities for the potent compounds. The 1,2,3-triazole derivative 27 substituted by a decyl tail, an undecyl spacer and a choline head group exhibited broad spectrum antiparasitic activity. It possessed low micromolar activity against the intracellular amastigotes of two L. infantum strains and T. cruzi Y strain epimastigotes, intracellular amastigotes and trypomastigotes, while its cytotoxicity concentration (CC50) against THP-1 macrophages ranged between 50 and 100 μM. Altogether, our work paves the way for the development of improved ether phospholipid derivatives to control neglected tropical diseases. 相似文献
79.
Morton JJ Tyryshkin AM Ardavan A Porfyrakis K Lyon SA Andrew D Briggs G 《The Journal of chemical physics》2006,124(1):14508
We examine the temperature dependence of the electron spin relaxation times of the molecules N@C60 and N@C70 (which comprise atomic nitrogen trapped within a carbon cage) in liquid CS2 solution. The results are inconsistent with the fluctuating zero-field splitting (ZFS) mechanism, which is commonly invoked to explain electron spin relaxation for S> or =1 spins in liquid solution, and is the mechanism postulated in the literature for these systems. Instead, we find an Arrhenius temperature dependence for N@C60 , indicating the spin relaxation is driven primarily by an Orbach process. For the asymmetric N@C70 molecule, which has a permanent ZFS, we resolve an additional relaxation mechanism caused by the rapid reorientation of its ZFS. We also report the longest coherence time (T2) ever observed for a molecular electron spin, being 0.25 ms at 170 K. 相似文献
80.
Deak DS Silly F Porfyrakis K Castell MR 《Journal of the American Chemical Society》2006,128(43):13976-13977
Developing useful molecular systems, such as planar networks for novel molecular electronics, requires the ability to control the way molecules assemble at surfaces. Here we report how an oxide crystal surface can be used as a template to controllably order endohedral fullerenes, Er3N@C80, into two-dimensional (2D) open-grid arrays. The crystal surface is made of highly ordered oxide nanostructures which self-assemble on the surface of SrTiO3(001). This method of molecular ordering can be applied to other fullerenes and has the potential to provide a basis for developing a wide range of molecular architectures. 相似文献